1. Field of the Invention
The present invention relates to a novel active hood system. More specifically, the present invention relates to a novel active hood system that softens the impact between the pedestrian and the vehicle hood during a pedestrian/vehicle collision.
2. Description of Related Art
Accidents in which a motor vehicle strikes a pedestrian present a serious health risk to pedestrians. In pedestrian/vehicle accidents, the heavier and larger motor vehicle impacts the smaller and lighter pedestrian with a significant amount of force. Depending on the speed and nature of the pedestrian/vehicle accident, this forcible impact between the pedestrian and the vehicle can seriously injure the pedestrian.
One type of pedestrian/vehicle accident that is particularly harmful occurs when the vehicle's front bumper or other frontal portion impacts the pedestrian's knee, leg, and/or abdominal region. Of course, this frontal impact harms the pedestrian's knee, leg, and/or abdominal region. Usually however, this frontal impact also elevates and/or flips the pedestrian such that the pedestrian's head strikes the vehicle's hood or windshield.
This second impact—the blow to the pedestrian's head—is particularly dangerous and can cause the pedestrian severe injury or trauma.
Unfortunately, the design of many currently motor vehicles can operate to heighten the severity of the impact between the pedestrian's head against the vehicle hood. For example, in vehicles such as low profile vehicles, the portion of the vehicle hood that is adjacent to the vehicle windshield is often made to be a very hard and rigid surface. Thus, if the pedestrian's head impacts this hard surface during an accident, the likelihood that the pedestrian will be injured is substantially increased.
Moreover, in order to improve the aerodynamics and visual aesthetics of the model, many vehicles are designed such that there is little or no gap between the vehicle hood and the engine that is covered by the hood. This is especially true in low profile or compact vehicle models. While this vehicle design may improve appearance, the fact that there is little or no gap between the hood and the engine means that there is little room for the hood to deform and dissipate some of the energy of the impact of the pedestrian torso and/or head. Rather, this vehicle design can actually intensify and/or focus the energy of the impact onto the pedestrian such that the likelihood of pedestrian injury is significantly increased.
Concerned about these and other safety hazards, many groups have lobbied to have additional regulations be placed upon vehicle manufacturers. Such regulations would require that all new vehicles include a safety system that is designed to protect and/or cushion the impact of a pedestrian during a pedestrian/vehicle collision. As a result of these lobbying efforts, there is now pending legislation in Korea, Japan, and Europe that would require that all new vehicles have some sort of pedestrian protection capability. The current schedule will have this legislation take effect some time between 2005 and 2010.
In order to prepare for this pending legislation, vehicle manufacturers have begun to research various safety systems and methods for protecting pedestrians during a pedestrian/vehicle collision. One type of safety system that has been particularly studied is the so-called “active hood system” which is designed such that in the event of a pedestrian/vehicle accident, the active hood system will raise all or a portion of the hood into an elevated position. By elevating the hood, the active hood system allows the hood to undergo greater deformation during the collision. In turn, this increased hood deformation allows the hood to dissipate a larger portion of the collision energy and reduces the overall severity of the impact between the pedestrian and the vehicle.
Further development indicates that in order to effectively position the hood during a collision, the active hood system must be configured to raise the hood into the elevated position within about 15 to 30 milliseconds. While such rapid movement of the hood may be achieved, such rapid movement of the hood may cause the hood to undesirably bounce or vibrate when the hood reaches the elevated position. Such bouncing of the hood is especially prone to occur in those active hood systems that do not include a dampener or other mechanism for slowing the movement of the hood.
Accordingly, there is a need in the art for a novel active hood system that addresses and/or solves one or more of the above-listed problems. Such a system and method is disclosed herein.